1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
riadik2000 [5.3K]
4 years ago
10

All isotopes of technetium are radioactive, but they have widely varying half-lives. If an 800.0 g sample of technetium-99 decay

s to 100.0 g of technetium-99 in 639 000 y. What is it's half-life?
Mathematics
1 answer:
erica [24]4 years ago
3 0
The formula for A = Ao (1/2) ^ t/h
So sub in.
100 = 800 (1/2) ^ 639,000/?
That's all i can do lol

You might be interested in
What is the solution of log(4-3) = log(17-41)?<br> O4<br> O 5<br> O 15<br> O 20
borishaifa [10]
<h3>Answer: Choice A) 4</h3>

Explanation:

The rule is that if log(A) = log(B), then A = B

Using this idea, we can then say,

log(t - 3) = log(17 - 4t)

t - 3 = 17 - 4t

t+4t = 17+3

5t = 20

t = 20/5

t = 4

3 0
3 years ago
Read 2 more answers
A young person decides to put aside some money for retirement by putting $1,000 in a 30-year savings bond that pays 3.0% simple
Pavel [41]

Answer:

2427.26 $

Step-by-step explanation:

Just use this formula when you have such type of problems:

N = N° (1 + %)^t

Where N = final amount

           N°= initial amount

           t = peroid of time

Now let's solve:

N = 1000(1 + 0.03)^30

N = 2427.26

5 0
3 years ago
Ava and Maria went shopping together. Eva spent $20 more than Maria. Together they spent $209.84. Write and solve an equation to
ad-work [718]

Answer:209.84 - 20.00 = 189.84 / 2 = 94.92

94.92 + 20.00 = 114.92 Eva spent and Martha spent $94.92

Step-by-step explanation:

5 0
3 years ago
Tommy can paint a fence in 6 hours. If his friend Huck helps, they can paint the fence in 1 hour. How fast could Huck paint the
Luda [366]
1hr/10min is the answer
8 0
3 years ago
The area of a garden is 8 3/4 square yards. If the lenght is 1 1/4 yards , what is the length?​
andrezito [222]

Answer:

The Missing Length = 7

Step-by-step explanation:

Equation: side length x side length = area

  • This means that if you divide the area by one of the side lengths, you'll find the other

1.  Convert the numbers into decimals

  • 8 3/4 -  8.75 (area)
  • 1 1/4  = 1.25 (side length)

2. Divide the <u>area</u> by the <u>side length</u>

  • 8.75 ÷ 1.25 = <u>7</u>

<u></u>

<u>7</u> is the answer.

6 0
3 years ago
Other questions:
  • What is the answer to -3x-3=3x-9
    14·1 answer
  • A right cylinder has a diameter of 30 mm and a height of 30 mm, as shown.
    8·1 answer
  • Elaine had 27 buttons. Her grandmother donated 6 cards of buttons to the collection. Elaine sorted the buttons into 9 piles, put
    7·1 answer
  • HELP PLEASE
    9·2 answers
  • the sum of two numbers is 63. the smaller number is 21 less than the larger number. what are the numbers
    14·2 answers
  • lissa has $75 worth of bird seed, which she will put into small bags. She will sell each bag for $7. What is the greatest number
    12·1 answer
  • Write a ratio to show the
    13·1 answer
  • Plz helpppp will mark brainliesttttt
    6·2 answers
  • X+3
    6·2 answers
  • Someone help me please
    5·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!